foundationdb/bindings/flow/DirectoryLayer.actor.cpp

508 lines
18 KiB
C++

/*
* DirectoryLayer.actor.cpp
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "DirectoryLayer.h"
#include "DirectoryPartition.h"
namespace FDB {
const uint8_t DirectoryLayer::LITTLE_ENDIAN_LONG_ONE[8] = {1,0,0,0,0,0,0,0};
const StringRef DirectoryLayer::HIGH_CONTENTION_KEY = LiteralStringRef("hca");
const StringRef DirectoryLayer::LAYER_KEY = LiteralStringRef("layer");
const StringRef DirectoryLayer::VERSION_KEY = LiteralStringRef("version");
const int64_t DirectoryLayer::SUB_DIR_KEY = 0;
const uint32_t DirectoryLayer::VERSION[3] = {1, 0, 0};
const StringRef DirectoryLayer::DEFAULT_NODE_SUBSPACE_PREFIX = LiteralStringRef("\xfe");
const Subspace DirectoryLayer::DEFAULT_NODE_SUBSPACE = Subspace(DEFAULT_NODE_SUBSPACE_PREFIX);
const Subspace DirectoryLayer::DEFAULT_CONTENT_SUBSPACE = Subspace();
const StringRef DirectoryLayer::PARTITION_LAYER = LiteralStringRef("partition");
DirectoryLayer::DirectoryLayer(Subspace nodeSubspace, Subspace contentSubspace, bool allowManualPrefixes) :
nodeSubspace(nodeSubspace), contentSubspace(contentSubspace), allowManualPrefixes(allowManualPrefixes),
rootNode(nodeSubspace.get(nodeSubspace.key())), allocator(rootNode.get(HIGH_CONTENTION_KEY))
{ }
Subspace DirectoryLayer::nodeWithPrefix(StringRef const& prefix) const {
return nodeSubspace.get(prefix);
}
template<class T>
Optional<Subspace> DirectoryLayer::nodeWithPrefix(Optional<T> const& prefix) const {
if(!prefix.present()) {
return Optional<Subspace>();
}
return nodeWithPrefix(prefix.get());
}
ACTOR Future<DirectoryLayer::Node> find(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path path) {
state int pathIndex = 0;
state DirectoryLayer::Node node = DirectoryLayer::Node(dirLayer, dirLayer->rootNode, IDirectory::Path(), path);
for(; pathIndex != path.size(); ++pathIndex) {
ASSERT(node.subspace.present());
Optional<FDBStandalone<ValueRef>> val = wait(tr->get(node.subspace.get().get(DirectoryLayer::SUB_DIR_KEY).get(path[pathIndex], true).key()));
node.path.push_back(path[pathIndex]);
node = DirectoryLayer::Node(dirLayer, dirLayer->nodeWithPrefix(val), node.path, path);
DirectoryLayer::Node _node = wait(node.loadMetadata(tr));
node = _node;
if(!node.exists() || node.layer == DirectoryLayer::PARTITION_LAYER) {
return node;
}
}
if(!node.loadedMetadata) {
DirectoryLayer::Node _node = wait(node.loadMetadata(tr));
node = _node;
}
return node;
}
IDirectory::Path DirectoryLayer::toAbsolutePath(IDirectory::Path const& subpath) const {
Path path;
path.reserve(this->path.size() + subpath.size());
path.insert(path.end(), this->path.begin(), this->path.end());
path.insert(path.end(), subpath.begin(), subpath.end());
return path;
}
Reference<DirectorySubspace> DirectoryLayer::contentsOfNode(Subspace const& node, Path const& path, Standalone<StringRef> const& layer) {
Standalone<StringRef> prefix = nodeSubspace.unpack(node.key()).getString(0);
if(layer == PARTITION_LAYER) {
return Reference<DirectorySubspace>(new DirectoryPartition(toAbsolutePath(path), prefix, Reference<DirectoryLayer>::addRef(this)));
}
else {
return Reference<DirectorySubspace>(new DirectorySubspace(toAbsolutePath(path), prefix, Reference<DirectoryLayer>::addRef(this), layer));
}
}
Reference<DirectorySubspace> DirectoryLayer::openInternal(Standalone<StringRef> const& layer, Node const& existingNode, bool allowOpen) {
if (!allowOpen) {
throw directory_already_exists();
}
if(layer.size() > 0 && layer != existingNode.layer) {
throw mismatched_layer();
}
return existingNode.getContents();
}
Future<Reference<DirectorySubspace>> DirectoryLayer::open(Reference<Transaction> const& tr, Path const& path, Standalone<StringRef> const& layer) {
return createOrOpenInternal(tr, path, layer, Optional<Standalone<StringRef>>(), false, true);
}
void DirectoryLayer::initializeDirectory(Reference<Transaction> const& tr) const {
tr->set(rootNode.pack(VERSION_KEY), StringRef((uint8_t*)VERSION, 12));
}
ACTOR Future<Void> checkVersionInternal(const DirectoryLayer* dirLayer, Reference<Transaction> tr, bool writeAccess) {
Optional<FDBStandalone<ValueRef>> versionBytes = wait(tr->get(dirLayer->rootNode.pack(DirectoryLayer::VERSION_KEY)));
if(!versionBytes.present()) {
if(writeAccess) {
dirLayer->initializeDirectory(tr);
}
return Void();
}
else {
if(versionBytes.get().size() != 12) {
throw invalid_directory_layer_metadata();
}
if(((uint32_t*)versionBytes.get().begin())[0] > DirectoryLayer::VERSION[0]) {
throw incompatible_directory_version();
}
else if(((uint32_t*)versionBytes.get().begin())[1] > DirectoryLayer::VERSION[1] && writeAccess) {
throw incompatible_directory_version();
}
}
return Void();
}
Future<Void> DirectoryLayer::checkVersion(Reference<Transaction> const& tr, bool writeAccess) const {
return checkVersionInternal(this, tr, writeAccess);
}
ACTOR Future<Standalone<StringRef>> getPrefix(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, Optional<Standalone<StringRef>> prefix) {
if(!prefix.present()) {
Standalone<StringRef> allocated = wait(dirLayer->allocator.allocate(tr));
state Standalone<StringRef> finalPrefix = allocated.withPrefix(dirLayer->contentSubspace.key());
FDBStandalone<RangeResultRef> result = wait(tr->getRange(KeyRangeRef(finalPrefix, strinc(finalPrefix)), 1));
if(result.size() > 0) {
throw directory_prefix_not_empty();
}
return finalPrefix;
}
return prefix.get();
}
ACTOR Future<Optional<Subspace>> nodeContainingKey(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, Standalone<StringRef> key, bool snapshot) {
if(key.startsWith(dirLayer->nodeSubspace.key())) {
return dirLayer->rootNode;
}
KeyRange range = KeyRangeRef(dirLayer->nodeSubspace.range().begin, keyAfter(dirLayer->nodeSubspace.pack(key)));
FDBStandalone<RangeResultRef> result = wait(tr->getRange(range, 1, snapshot, true));
if(result.size() > 0) {
Standalone<StringRef> prevPrefix = dirLayer->nodeSubspace.unpack(result[0].key).getString(0);
if(key.startsWith(prevPrefix)) {
return dirLayer->nodeWithPrefix(prevPrefix);
}
}
return Optional<Subspace>();
}
ACTOR Future<bool> isPrefixFree(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, Standalone<StringRef> prefix, bool snapshot){
if(!prefix.size()) {
return false;
}
Optional<Subspace> node = wait(nodeContainingKey(dirLayer, tr, prefix, snapshot));
if(node.present()) {
return false;
}
FDBStandalone<RangeResultRef> result = wait(tr->getRange(KeyRangeRef(dirLayer->nodeSubspace.pack(prefix), dirLayer->nodeSubspace.pack(strinc(prefix))), 1, snapshot));
return !result.size();
}
ACTOR Future<Subspace> getParentNode(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path path) {
if(path.size() > 1) {
Reference<DirectorySubspace> parent = wait(dirLayer->createOrOpenInternal(tr, IDirectory::Path(path.begin(), path.end() - 1), StringRef(), Optional<Standalone<StringRef>>(), true, true));
return dirLayer->nodeWithPrefix(parent->key());
}
else {
return dirLayer->rootNode;
}
}
ACTOR Future<Reference<DirectorySubspace>> createInternal(
Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path path,
Standalone<StringRef> layer, Optional<Standalone<StringRef>> prefix, bool allowCreate)
{
if(!allowCreate) {
throw directory_does_not_exist();
}
wait(dirLayer->checkVersion(tr, true));
state Standalone<StringRef> newPrefix = wait(getPrefix(dirLayer, tr, prefix));
bool isFree = wait(isPrefixFree(dirLayer, tr, newPrefix, !prefix.present()));
if(!isFree) {
throw directory_prefix_in_use();
}
Subspace parentNode = wait(getParentNode(dirLayer, tr, path));
Subspace node = dirLayer->nodeWithPrefix(newPrefix);
tr->set(parentNode.get(DirectoryLayer::SUB_DIR_KEY).get(path.back(), true).key(), newPrefix);
tr->set(node.get(DirectoryLayer::LAYER_KEY).key(), layer);
return dirLayer->contentsOfNode(node, path, layer);
}
ACTOR Future<Reference<DirectorySubspace>> _createOrOpenInternal(
Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path path,
Standalone<StringRef> layer, Optional<Standalone<StringRef>> prefix, bool allowCreate, bool allowOpen)
{
ASSERT(!prefix.present() || allowCreate);
wait(dirLayer->checkVersion(tr, false));
if(prefix.present() && !dirLayer->allowManualPrefixes) {
if(!dirLayer->getPath().size()) {
throw manual_prefixes_not_enabled();
}
else {
throw prefix_in_partition();
}
}
if(!path.size()){
throw cannot_open_root_directory();
}
state DirectoryLayer::Node existingNode = wait(find(dirLayer, tr, path));
if(existingNode.exists()) {
if(existingNode.isInPartition()) {
IDirectory::Path subpath = existingNode.getPartitionSubpath();
Reference<DirectorySubspace> dirSpace = wait(existingNode.getContents()->getDirectoryLayer()->createOrOpenInternal(tr, subpath, layer, prefix, allowCreate, allowOpen));
return dirSpace;
}
return dirLayer->openInternal(layer, existingNode, allowOpen);
}
else {
Reference<DirectorySubspace> dirSpace = wait(createInternal(dirLayer, tr, path, layer, prefix, allowCreate));
return dirSpace;
}
}
Future<Reference<DirectorySubspace>> DirectoryLayer::createOrOpenInternal(
Reference<Transaction> const& tr, Path const& path, Standalone<StringRef> const& layer,
Optional<Standalone<StringRef>> const& prefix, bool allowCreate, bool allowOpen)
{
return _createOrOpenInternal(Reference<DirectoryLayer>::addRef(this), tr, path, layer, prefix, allowCreate, allowOpen);
}
Future<Reference<DirectorySubspace>> DirectoryLayer::create(
Reference<Transaction> const& tr, Path const& path, Standalone<StringRef> const& layer,
Optional<Standalone<StringRef>> const& prefix)
{
return createOrOpenInternal(tr, path, layer, prefix, true, false);
}
Future<Reference<DirectorySubspace>> DirectoryLayer::createOrOpen(Reference<Transaction> const& tr, Path const& path, Standalone<StringRef> const& layer) {
return createOrOpenInternal(tr, path, layer, Optional<Standalone<StringRef>>(), true, true);
}
ACTOR Future<Standalone<VectorRef<StringRef>>> listInternal(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path path) {
wait(dirLayer->checkVersion(tr, false));
state DirectoryLayer::Node node = wait(find(dirLayer, tr, path));
if(!node.exists()) {
throw directory_does_not_exist();
}
if(node.isInPartition(true)) {
Standalone<VectorRef<StringRef>> partitionList = wait(node.getContents()->getDirectoryLayer()->list(tr, node.getPartitionSubpath()));
return partitionList;
}
state Subspace subdir = node.subspace.get().get(DirectoryLayer::SUB_DIR_KEY);
state Key begin = subdir.range().begin;
state Standalone<VectorRef<StringRef>> subdirectories;
loop {
FDBStandalone<RangeResultRef> subdirRange = wait(tr->getRange(KeyRangeRef(begin, subdir.range().end)));
for(int i = 0; i < subdirRange.size(); ++i) {
subdirectories.push_back_deep(subdirectories.arena(), subdir.unpack(subdirRange[i].key).getString(0));
}
if(!subdirRange.more) {
return subdirectories;
}
begin = keyAfter(subdirRange.back().key);
}
}
Future<Standalone<VectorRef<StringRef>>> DirectoryLayer::list(Reference<Transaction> const& tr, Path const& path) {
return listInternal(Reference<DirectoryLayer>::addRef(this), tr, path);
}
bool pathsEqual(IDirectory::Path const& path1, IDirectory::Path const& path2, size_t maxElementsToCheck = std::numeric_limits<size_t>::max()) {
if(std::min(path1.size(), maxElementsToCheck) != std::min(path2.size(), maxElementsToCheck)) {
return false;
}
for(int i = 0; i < path1.size() && i < maxElementsToCheck; ++i) {
if(path1[i] != path2[i]) {
return false;
}
}
return true;
}
ACTOR Future<Void> removeFromParent(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path path) {
ASSERT(path.size() >= 1);
DirectoryLayer::Node parentNode = wait(find(dirLayer, tr, IDirectory::Path(path.begin(), path.end() - 1)));
if(parentNode.subspace.present()) {
tr->clear(parentNode.subspace.get().get(DirectoryLayer::SUB_DIR_KEY).get(path.back(), true).key());
}
return Void();
}
ACTOR Future<Reference<DirectorySubspace>> moveInternal(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path oldPath, IDirectory::Path newPath) {
wait(dirLayer->checkVersion(tr, true));
if(oldPath.size() <= newPath.size()) {
if(pathsEqual(oldPath, newPath, oldPath.size())) {
throw invalid_destination_directory();
}
}
std::vector<Future<DirectoryLayer::Node>> futures;
futures.push_back(find(dirLayer, tr, oldPath));
futures.push_back(find(dirLayer, tr, newPath));
std::vector<DirectoryLayer::Node> nodes = wait(getAll(futures));
state DirectoryLayer::Node oldNode = nodes[0];
state DirectoryLayer::Node newNode = nodes[1];
if(!oldNode.exists()) {
throw directory_does_not_exist();
}
if(oldNode.isInPartition() || newNode.isInPartition()) {
if(!oldNode.isInPartition() || !newNode.isInPartition() || !pathsEqual(oldNode.path, newNode.path)) {
throw cannot_move_directory_between_partitions();
}
Reference<DirectorySubspace> partitionMove = wait(newNode.getContents()->move(tr, oldNode.getPartitionSubpath(), newNode.getPartitionSubpath()));
return partitionMove;
}
if(newNode.exists() || newPath.empty()) {
throw directory_already_exists();
}
DirectoryLayer::Node parentNode = wait(find(dirLayer, tr, IDirectory::Path(newPath.begin(), newPath.end() - 1)));
if(!parentNode.exists()) {
throw parent_directory_does_not_exist();
}
tr->set(parentNode.subspace.get().get(DirectoryLayer::SUB_DIR_KEY).get(newPath.back(), true).key(), dirLayer->nodeSubspace.unpack(oldNode.subspace.get().key()).getString(0));
wait(removeFromParent(dirLayer, tr, oldPath));
return dirLayer->contentsOfNode(oldNode.subspace.get(), newPath, oldNode.layer);
}
Future<Reference<DirectorySubspace>> DirectoryLayer::move(Reference<Transaction> const& tr, Path const& oldPath, Path const& newPath) {
return moveInternal(Reference<DirectoryLayer>::addRef(this), tr, oldPath, newPath);
}
Future<Reference<DirectorySubspace>> DirectoryLayer::moveTo(Reference<Transaction> const& tr, Path const& newAbsolutePath) {
throw cannot_modify_root_directory();
}
Future<Void> removeRecursive(Reference<DirectoryLayer> const&, Reference<Transaction> const&, Subspace const&);
ACTOR Future<Void> removeRecursive(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, Subspace nodeSub) {
state Subspace subdir = nodeSub.get(DirectoryLayer::SUB_DIR_KEY);
state Key begin = subdir.range().begin;
state std::vector<Future<Void>> futures;
loop {
FDBStandalone<RangeResultRef> range = wait(tr->getRange(KeyRangeRef(begin, subdir.range().end)));
for (int i = 0; i < range.size(); ++i) {
Subspace subNode = dirLayer->nodeWithPrefix(range[i].value);
futures.push_back(removeRecursive(dirLayer, tr, subNode));
}
if(!range.more) {
break;
}
begin = keyAfter(range.back().key);
}
// waits are done concurrently
wait(waitForAll(futures));
Standalone<StringRef> nodePrefix = dirLayer->nodeSubspace.unpack(nodeSub.key()).getString(0);
tr->clear(KeyRangeRef(nodePrefix, strinc(nodePrefix)));
tr->clear(nodeSub.range());
return Void();
}
Future<bool> removeInternal(Reference<DirectoryLayer> const&, Reference<Transaction> const&, IDirectory::Path const&, bool const&);
ACTOR Future<bool> removeInternal(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path path, bool failOnNonexistent) {
wait(dirLayer->checkVersion(tr, true));
if(path.empty()) {
throw cannot_modify_root_directory();
}
state DirectoryLayer::Node node = wait(find(dirLayer, tr, path));
if(!node.exists()) {
if(failOnNonexistent) {
throw directory_does_not_exist();
}
else {
return false;
}
}
if(node.isInPartition()) {
bool recurse = wait(removeInternal(node.getContents()->getDirectoryLayer(), tr, node.getPartitionSubpath(), failOnNonexistent));
return recurse;
}
state std::vector<Future<Void>> futures;
futures.push_back(removeRecursive(dirLayer, tr, node.subspace.get()));
futures.push_back(removeFromParent(dirLayer, tr, path));
wait(waitForAll(futures));
return true;
}
Future<Void> DirectoryLayer::remove(Reference<Transaction> const& tr, Path const& path) {
return success(removeInternal(Reference<DirectoryLayer>::addRef(this), tr, path, true));
}
Future<bool> DirectoryLayer::removeIfExists(Reference<Transaction> const& tr, Path const& path) {
return removeInternal(Reference<DirectoryLayer>::addRef(this), tr, path, false);
}
ACTOR Future<bool> existsInternal(Reference<DirectoryLayer> dirLayer, Reference<Transaction> tr, IDirectory::Path path) {
wait(dirLayer->checkVersion(tr, false));
DirectoryLayer::Node node = wait(find(dirLayer, tr, path));
if(!node.exists()) {
return false;
}
if(node.isInPartition()) {
bool exists = wait(node.getContents()->getDirectoryLayer()->exists(tr, node.getPartitionSubpath()));
return exists;
}
return true;
}
Future<bool> DirectoryLayer::exists(Reference<Transaction> const& tr, Path const& path) {
return existsInternal(Reference<DirectoryLayer>::addRef(this), tr, path);
}
Reference<DirectoryLayer> DirectoryLayer::getDirectoryLayer() {
return Reference<DirectoryLayer>::addRef(this);
}
const Standalone<StringRef> DirectoryLayer::getLayer() const {
return StringRef();
}
const IDirectory::Path DirectoryLayer::getPath() const {
return path;
}
}